Find all complex numbers z satisfying

z3 = 27i

and give your answer as a comma-separated list of values in the form a+bi.

1 answer

z^3 = 27i
z = 3?i

i = 1 cis(?/2)
?i = cis((1/3)*(?/2 + 2k?)) for k=0,1,2
= cis ?/6, 5?/6, 9?/6

See

http://www.wolframalpha.com/input/?i=z%5E3+%3D+27i